Tamping machine



y 2, 1956 w. T. FERGUSON 2,746,367

TAMPING MACHINE Filed Sept. 27, 1951 2 Sheets-Sheet l Z 7zde7zZo2-= ZJZZZZ'Q'WZZYZW asozz y 2, 1956 w. T. FERGUSON 2,746,367

TAMPING MACHINE Filed Sept. 27, 1951 2 Sheets-Sheet 2 five 72207:

Z" e yzzsazz United States PatentO 2,746,367 I TAMl'lNG MACHINE William T. Ferguson, Bell, CalifQ, assignor, by mesne as- I "signinents, to Edna G. Ferguson, Bell Gardens, Calif.

Application September 27, 1951, Serial No. 248,590

8 Claims. cram-49 portion to the size of the tamping member; to provide a 'more rapidly operating tamping machine which will efficiently tamp a plastic cementitious surface while the workman pulls or pushes the same thereacross at a rapid walk; and to provide a tamping machine wherein a pair of horizontally spaced apart shoes support the framework of the machine upon the surface being tamped with the tamper and its operating mechanism located between said shoes, thus affording a more stable and satisfactory means for portably mounting the machine in such amanner that,

' While the tamping member is efliciently operated the shoes are at the same time tiltingly vibrated so that they manipulate the plastic cement underlying them and a smoother surface is imparted to said surface of said cement. M

By the operation of a machine constructed according to the principles .of this invention more fine material 'is brought up to the surface and the possibility is eliminated of holes occurring that might result fromthe use of a Other objects, advantages and features of invention will hereinafter appear.

Referring to the drawings wherein is shown a preferred,

reduced to practice, embodiment of theinvention,

Fig. 1 is a top plan view with some portions broken away to show underlying structure.

Fig. 2 is a front elevation. i g Fig; 3 is a side elevation on a smaller scale.

Fig. 4 is an enlarged fragmentary section on line 4-4 ofFig. 1. j a Fig. 5 is a section on line 5--5 of Fig. 4.

Referring in detail to the drawings, the device comprises an upstanding skeletal framework 6 consisting of a front, tubular member 7 shaped as a broad, approximately rectangular inverted U and a twin rear member 8. Said U-shaped members are in the parallel spaced apart relation to each other shown, and are rigidly maintained in this relation by means of a pair of angle iron members 9 and 10, the inner angles of which are directed downwardly and toward each other, the inner edges of the flanges of each of said angle irons contacting with and being welded to the outer corner portions of said U-shaped members.

ice

.The function of these guide members will be set forth later.

A pair of horizontally spaced apart shoes, preferably of #16 gage sheet metal, 18 is providedto rest upon the surface of the plastic, cementitious material to be treated by the machine, the function of said shoes being to floatably support the weight of the machine upon such a surface. Each of said shoes is dish shaped, preferably having an upwardly directed marginal flange portion 18a at each end and an outer, upwardly deflected flange 19. Said shoes are thus provided with upturned marginal portions adapting them to act as floats to support the super-structure of the device upon soft cement, and also guarding against said shoes digging into the cement when the Ina-v shoes. The flanges 20 are secured respectively to tubular members 7 and 8 by appropriate conventional means as,

, for example, by welding. A sectional cover member 21 overlies and bridges the space between said upstanding flanges, said cover member having at each side a downwardly directed flange 22 which .is bolted to the aforesaid upstanding flange 20 at its side of the structure. The bolts23 which secure the flanges of said cover member to the aforesaid upstanding flanges 20 have at their inner ends flat heads which are countersunk so as to present a smooth surface on the inner faces of said flanges 20. By this arrangement an alcove 24 is provided under said cover plate 21, and in this alcove is mounted a vertically reciprocatory tamper 25.

Said tamper 25 comprises a reticulated horizontal bottom member 26, made of expanded sheet metal and having reticulations dimensioned to allow ready penetration J of the cementitious material, but which are sufficiently small not to interfere with said bottom member 26 embedding into the plastic cement any solid particles that would otherwise prevent'troweling of the surface of the plastic cement'into a smooth condition. The reticulated sheet metal of the tamper engages the plastic cementin an edgewise manner.

To' the upper surface of the reticulated metal 26 is welded a plurality of parallel, spaced apart spacers comprising outer spacers 27, which aline with the outer ends of the reticulated member 26, and intermediate spacers 28 which'are equally spaced between said outer spacers 27. All of said spacers have welded to their outer edges a tie plate 29 at each side of the framework. Said tie plates each span and bridge over the interval between said spacers and lock the upper edges of said spacers to said tie plates 29. To the midlength portion of the upper sur- .face of each of said tie plates is welded one end' of a lock the threaded end of said rod 31 in its fully screwed in position.

Said framework comprises, in addition to its aforesaid Each of said rods 31 projects upwardly through an aperture 21a in the cover plate 21 and then passes loosely through the axial passage of the aforesaid tubular guide member 16 or 17 at its side of the structure. Each of said rods 31 is provided at one end with an eyeletted end portion which .is straddled by a bifurcated yoke 33 of a turnbuckle type, into the upper end of said yoke being screwed the threaded end of a rod 34, the upper end .of this rod being roller-bearingly connected to an eccentn'c pin 36 carried by a crank arm 37, said crank arm having its opposite end portion secured to a stub shaft 38.

Said stub shaft is telescoped into and welded to the tubular driving shaft 39, the latter being supported at its ends by aluminum pillar blocks 40 secured to the aforesaid angle irons 9 and 10. V

Said driving shaft 39 carries a V-shaped pulley 41, preferably of pressed wood, over which passes a V-shaped belt 42 connected to an automatic clutch driving mechanism 43 of a conventional character, which is automatically engaged and disengaged in accordance with the speed of the motor. Said clutch is driven by the motor shaft 44, in turn operated by the conventional motor45. Said motor includes the usual starting pulley 46, air filter 47, gas tank 48 and other conventional accessories.

Against the screwed on end of each of the aforesaid yokes 33 abuts a lock nut 55. These lock nuts enable the workman, after he has screwed said yokes onto the rods 34 to the desired extent, to lock said yokes in the adjusted position. Provision is thus made for adjusting the limit of the downward movements of the verticallyreeiprocable tamper 25 below the bottom surfaces of the shoes as is necessary to obtain its proper operation.

In order to propel the device over the plastic cement, it is manually pulled or pushed by a tubular U-shaped handle member 59 having arms and 59h adjustably telescoped into a pair of sleeves 60, the lower ends of which are welded to the upstanding arms of the U-shaped membet 8, tubular brace members 61 being used to connect said inclined brace members 60 to the upper portions of said U-shaped. member 8. The aforesaid sleeves 60 are provided with a longitudinally extending series of apertures 62 and the aforesaid arms 59a, 59b of the handle member 59 are likewise apertured to mate with said apertures of said sleeves, wing nut bolts 63 being used to adjustably secure said operating handle in selected adjusted positions.

It will be observed, by looking at Fig. 2, that the cover plate 21 is divided into a longitudinally extending series of abutting sections, namely, twin outer sections 65, twin intermediate sections 66 and a central section 67, this being necessary to facilitate assembling.

I Where the flange portions 22 of the aforesaid sectional cover member 21 come opposite to the upright arms of the U members 7 and .8, said flanges are coped out as indicated at 68 to permit the welding of said arms directly to the upturned flanges 20 of the shoes, this being shown in Fig. 2.

During the operation of said tamper each time the rods 31 are moved downwardly by the eccentric 37, said rods (assuming that the pulley 41 is turning in a clockwise direction as viewed in Fig. 3), will create opposed lateral thrusts against the right and left sides of the bore of the guide members 16 or 17 through which said rods 31 vertically reciprocate. These alternate impacts will cause the shoes 18 to vibrate in such a manneras to cause the underlying cement to be churned into a soupy condition, which eliminates the necessity of redressing the surface of the cement with a bull float. If desired, the shoes 18 can be weighted to add to the eificiency of their operation.

I claim:

1. A tamping machine comprising an upstanding skeletal framework, a pair of horizontally spaced apart shoes which are rigidly fixed upon opposite side portions of said framework, said shoes having spacious flat bottom surfaces adapted to ride upon a horizontal cementitious plastic surface, a tamper substantially filling the space between said' shoes, said tamper having a reticulated cement engaging portion of a suflicient fineness to obstruct objectionably large solid bodies in the cement, and motor driven means carried by said framework and said shoes and operatively connected to said tamper to impart a vertical reciprocatory movement to the latter, thus to embed the aforesaid solid bodies in the plastic cement.

2. The subject matter of claim 1 and said motor driven means including an eccentric driven member, linkage con- 4 necting said eccentric member to said tamper, an elongated guide rigidly'secured in vertical position to said framework and having a sliding engagement with a portion of said linkage, whereby said portion vertically reciprocates and has a double opposed lateral thrust against the guide at each reciprocation, thus creating a tilting vibration to said framework and in turn to said shoes.

3. A tamping machine comprising an upstanding skeletal framework, a pair of horizontally spaced apart shoes which are rigidly secured to opposite side portions of said framework respectively on forward and rearward sides of the frame, said shoes'having spacious bottom surfaces and curved outer edges to engage a horizontal cementitious plastic surface, and motor driven means carried by said framework comprising an eccentric mounted to operate forwardly and rearwardly, a rod extending downwardly from the eccentric, and a tubular guide on the frame slidably receiving said rod and resistant to fore and aft thrust of the rod whereby motion of the rod is adapted to impart a tilting vibration to said framework which vibration is communicated thereby to said shoes in alternation.

4. In a tamping maching of the kind described, a pair of opposed, spaced apart horizontally extending shoes adapted to be fioatably supported upon a bed of plastic cementitious material, a framework rigidly supported upon said shoes, a tamper carried by said framework and positioned to tamp the cementitious material underlying the space between said shoes, a vertically extending rod having its lower end in, a secured relation to said tamper, a vertically elongated guide sleeve rigidly mounted on said framework in a surrounding, annularly spaced relation to said rod, motor driven means on the frame and a crank between said motor driven means and said rod, said motor driven means being adapted for reciprocating said rod in said guide sleeve whereby an eccentrically tilting motion is imparted to said shoes simultaneously with moving said tamper up and down.

5. A tamping machine comprising an upstanding skeletal framework, a pair of horizontally spaced apart shoes the members of which are rigidly secured to lower ends of opposite side portions of said framework, said shoes having spacious bottom surfaces to engage a horizontal cernentitious plastic surface, a vertically reciprocating tamper mounted upon said framework .in a position substantially filling the area between said shoes and adapted to tamp the portion of the plastic surface Within said area, and mechanically operated eccentric means mounted upon said framework for movement in a vertical plane, said means having a vertically reciprocating rod .operatively connected to said tamper so as to vertically reciprocate the latter, said eccentric means being operable at the same time to tiltingly vibrate said shoes, and a vertically elongated confining guide rigidly secured to the framework having a vertically sl-idable engagement with said rod.

6. A tamping and finishing machine comprising a frame, a finishing plate secured at the bottom of the frame comprising a pair of shoes having smooth lower surfaces and adapted to support the machine on a surface of soft concrete, said shoes having inner edges defining opposite sides of a space between the shoes, 21 motor mounted upon and carried by the frame at a location above said area, a flat surfaced tamper substantially filling said area, vertically elongated horizontally confining guide means for the tamper rigidly mounted in the frame and sliding means on the tamper extending upwardly in sliding engagement with the guide means andadapted to accommodate vertical reciprocating movement of the tamper between positions below and above the level of the smooth lower surfaces of said shoes, said motor having a substantially horizontal shaft, an eccentric on the shaft and a linkage between the eccentric and the sliding means adapted to transfer motion of the eccentric to the tamper.

7. A tamping and finishing machine comprising a frame, a finishing plate secured at the bottom of the frame comprising a pair of shoes having broad smooth lower surfaces and adapted to support the machine on a surface of soft concrete, said shoes having inner edges defining opposite sides of a space between the shoes, a

1 motor mounted upon and carried by the frame at a location above said area, a flat surfaced tamper of relatively light construction substantially filling said area, vertically elongated horizontally confining guides rigidly mounted on the frame adapted to accommodate vertical reciprocating movement of the tamper between positions below and above the smooth lower surfaces of said shoes, said motor having a shaft, eccentric means on the shaft and, i

frame, a finishing plate secured to the bottom of the frame comprising a pair of shoes having broad smooth lower surfaces and adapted to support the machine on a surface of soft concrete, said shoes having inner upstanding flanges-defining opposite, sides of a substantially rectangular space between the shoes and a cover member over the tops of the flanges closing the top of said area, a motor rigidly mounted upon and carried by the frame at a location above said area, a fiat surface tamper of relatively light construction substantially filling said area,

vertically elongated confining guides for opposite sides of the tamper and sliding elements on the tamper adjacent said opposite sides of the tamper extending upwardly in horizontally confined sliding engagement with the guides and adapted to accommodate vertical reciprocating movement of the tamper betweenpositions below and above the level of the smooth lower surfaces of said shoes, said motor having a shaft with ends at opposite sides of the frame, an eccentric member on each end of the shaft and a link between each eccentric member and the sliding element at the corresponding side of the tamper.

References Cited in the file of this patent UNITED STATES PATENTS Layne Sept. 3, 1901 636,389 Germany 1936 

